CS327E - Data Models

Week 1

What is a database, fundamentally?

An organized collection of data that can be efficiently stored and retrieved

What is a Database Management System (DBMS) ?

A software system that creates, manages, and manipulates databases, abstracting hardware complexity from the user.

Why is database NOT just a better spreadsheet?

A database organizes related data by splitting and avoiding repetition, so questions can be answered efficiently

What does a data model specify?

Structure, Manipulation, Integrity

What characterizes a Flat-file database model?

Data stored in a single file with uniform record format, no explicit structures for relationships

What is the key structural feature of the Hierarchical database model?

Data organized into a tree-like structure connected via parent-child links (1:M)

How does the Network database model differ from Hierarchical model?

Its schema isn’t restricted to a hierarchy - it’s a graph of nodes and directed edges (no cycles)

How does the Relational database model organize data?

Into tables (relations) of rows and columns, where tables can be linked to each other

What language do most RDBMS use for querying and maintenance?

SQL

Name the five major components of RDBMS organization discussed

Data storage, Metadata, Schema, Query, Processor, Memory Manager

What defines a NoSQL database?

A data/storage retrieval mechanism modeled by means other than tabular relations, often called ‘Not only SQL’

MongoDB is what type of NoSQL database?

Document Database - stores flexible JSON-like documents

In relational databases, what type of consistency and scalability are typical?

Strong consistency (ACID) and vertical scalability (bigger server)

According to the comparison table what are typical use cases for NoSQL vs. Relational databases?

NoSQL: social media, IoT, real-time analytics, unstructured data.

Relational: banking, ERP, structured business data